Most of the cheap PWM solar charge controllers include a switched output that can turn lights on at sunset and and off after a specified time. Under $10 with USB outputs for charging gadgets and LCD display for voltage and status. Any car battery that still holds a charge should be enough to run LED lighting.

 

One more option for controlling the lights would be a motion sensor to switch the mains power to the 12 volt supply. But probably you will need to find one with a relay output instead of a triac output., because a switcher supply probably wants a close to AC feed. It may not matter with a transformer 12 volt supply. The benefit is that even if the lights are much brighter than needed they will not stay on more than half an hour.

 

Well, I should receive my LED's today. I have the 18 gauge wire already and I have the 12V supplies a-plenty. I also have a timer that I can set to run the SMPS. I DO have two car batteries kicking around that I've kept charged over the years, so that would work too, but then I would probably not want to use the 12V unless I modify it to 13.6V and use a light sensor switch for the low side. Another $12 investment and I'd have everything I've been considering hooking up.

Thanks all.

 

HardyMaria Thank you for the input. I've already completed my project. I'm only using a 12 volt transformer and a light sensor from Amazon to turn the lights on and off automatically. Funny, I get these grand notions and then end up going simple. OK, so they don't light up during a power failure. That's OK. We rarely have outages. And if one occurs I'll just deal with it. But thanks.